40fps at 40Hz vs 40fps at 120Hz small argument with Plasma TV for Gaming

[krisdee1981]

Hello everybody. Yesterday i have had small argument with youtuber called Plasma TV for Gaming.
During his live stream he has said that locked 40fps games (like for example Spiderman on PS5) at 120Hz will give you triple images and look terrible , so I asked him this question:

@KrisDee1981
22 godziny temu
Ariel I'm guessing you're talking about triple images with BFI?
40fps at 120Hz without BFI looks exactly the same like 40fps in 40Hz or 80Hz, but you will get less input lag.
Low frame rates have lower input lag at higher Hz. Even 240Hz still reduces 30fps latency. That's because the 30fps frames are refreshed faster in 1/240sec, allowing you to see the whole frame sooner.

@plasmatvforgaming9648
22 godziny temu
40fps at 120Hz will give you triple images regardless of BFI or not. For each frame the display is refreshing 3 times, that produces triple images. The only way to get it fix is with VRR 40fps/Hz

@KrisDee1981
22 godziny temu
Hate to tell you, but you are absolutely wrong about this.

@KrisDee1981
21 godzin temu
If you don't trust me, here you have your guru:
"Re: 240hz on 60FPS games
Post by Chief Blur Buster » 28 Feb 2018

On sample-and-hold displays, painting a 2nd image has no visible effect.
It just looks like a longer refresh cycle instead of multiple shorter refresh cycles.

However, if you're using LightBoost (ie. ONLY when strobing is enabled), THEN there is an effect
60fps at 120Hz LightBoost = 2 images
40fps at 120Hz LightBoost = 3 images
30fps at 120Hz LIghtBoost = 4 images.

However, for sample-and-hold, persistence is frame visibility time.
120Hz displays have 8ms persistence when running at full 120fps.
However, 240Hz displays also have 8ms persistence when running at 120fps too -- half framerates will have more motion blur.

So 120fps@120Hz and 120fps@240Hz has the same amount of motion blur and same amount of smoothness."


@plasmatvforgaming9648
10 godzin temu
Just test it, set the display to 120 Hz no BFI and cap the fps to 40, you'll see triple images.

@plasmatvforgaming9648
10 godzin temu
Only single refreshes of the same frame improve motion clarity regardless of BFI or not. Again, test it, and you'll see it clear

@plasmatvforgaming9648
10 godzin temu
You might be misinterpreting the chief




This guy talks about Blur Buster Law almost in every video for more then one year, and he still doesn't understand basics how sample and hold displays works. I have invited him to this forum, so we can figure out who is right, but I don't think he will show up, because now he deleted my comments.

[RealNC]

If he has one of those 960FPS smart phone cameras, the answer will be easy. Just record some footage and check for visible changes in the duration of the three frames being scanned out. There won't be any, unless the display is either using BFI or PWM backlighting (which for modern displays is rare,) or it's an OLED that uses rolling scan, which is OLED's equivalent for BFI. (Or a CRT of course, which also uses rolling scan.)

[krisdee1981]

Of course we were talking only about sample and hold displays like LG OLED (he has C1), or LCDs. Bfi or strobing disabled.